Response compression for the Website service (#7)

This PR contains the work done to add response compression to the Website service by registering the `ResponseCompressionMiddleware` middleware so responses are compressed when the client advertises support and the body exceeds a minimum size.

To provide further details about the work done:

* Added the **HummingbirdCompression** package dependency.
* Integrated the `ResponseCompressionMiddleware` middleware into the router, ahead of the not-found and static file middleware.
* Made the `minimum-response-size-to-compress` threshold configurable, with a default.

Reviewed-on: rock-n-code/loud-amsterdam#7
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>

Services/Website/Tests/App/AppTests.swift

@@ -71,6 +71,33 @@ struct AppTests {
         }
     }
 
+    @Test
+    func `response to be compressed when the client supports it`() async throws {
+        try await app.test(.router) { client in
+            try await client.execute(
+                uri: "/",
+                method: .get,
+                headers: [.acceptEncoding: "gzip"]
+            ) { response in
+                #expect(response.status == .ok)
+                #expect(response.headers[.contentEncoding] == "gzip")
+            }
+        }
+    }
+
+    @Test
+    func `response to not be compressed when the client does not support it`() async throws {
+        try await app.test(.router) { client in
+            try await client.execute(
+                uri: "/",
+                method: .get
+            ) { response in
+                #expect(response.status == .ok)
+                #expect(response.headers[.contentEncoding] == nil)
+            }
+        }
+    }
+
     @Test
     func `error page to be served when not found`() async throws {
         try await app.test(.router) { client in